Update: Using C++26 with contracts enabled

support/CMakeLists.txt

@@ -0,0 +1,8 @@
+add_library(course_contract_support STATIC contract_handler.cpp)
+target_compile_features(course_contract_support PUBLIC cxx_std_26)
+set_target_properties(course_contract_support PROPERTIES POSITION_INDEPENDENT_CODE ON)
+
+if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND COURSE_ENABLE_CONTRACTS)
+    target_compile_options(course_contract_support PRIVATE -fcontracts)
+    target_link_options(course_contract_support PRIVATE -fcontracts)
+endif()

support/contract_handler.cpp

@@ -0,0 +1,6 @@
+#include <contracts>
+#include <cstdlib>
+
+void handle_contract_violation(const std::contracts::contract_violation&) {
+    std::abort();
+}